1. Field of the Invention
The present invention relates to a mode switch device for a magnetic recording and reproducing apparatus such as a slide loading type camcorder, and more particularly to a mode switch device for a magnetic recording and reproducing apparatus, capable of having both the mode sensing function and the cassette holder ejecting function.
2. Description of the Prior Art
In conventional magnetic recording and reproducing apparatus employing a general slide loading system, there are provided a mode switch unit for sensing a mode of a tape cassette and a cassette holder ejecting unit for ejecting a cassette holder. These units are arranged separately from each other, to be driven individual driving sources.
As a result, wiring for connecting the units to a circuit board of the apparatus becomes .complex, resulting in degradations in workability in assembling and productivity. Moreover, there is an increase in the manufacture cost, since a separate sensing device is required.
FIG. 1 is a perspective view of a deck mechanism employing conventional arrangements of a mode switch unit and cassette holder ejecting unit. In the drawing, the reference character A denotes the deck mechanism. Also, the reference numerals B and C denote a mode switch unit and a cassette holder ejecting unit, respectively.
As shown in FIG. 1, the mode switch unit B and the cassette holder ejecting unit C are disposed separately from each other so that the mode switch unit B performs only the mode sensing operation, while the cassette holder ejecting unit C is driven by a separate driving source, to release a locked state of its lock lever and thus eject a cassette holder associated therewith.
FIG. 2 is an exploded perspective view of the construction of the conventional mode switch unit. As shown in FIG. 2, the mode switch unit comprises a base plate 1 bearing a mode sensing pattern (not shown) and having a predetermined shape. Beneath the base plate 1, a sensing gear 2 is rotatably mounted, which is provided with a mode sensing brush 2a. Over the base plate 1, a holder 3 is also coupled to the base plate 1. The mode switch unit with the above-mentioned construction is arranged to be engaged with a loading gear (not shown) of the deck mechanism. As the loading gear rotates, the sensing gear rotates, so that the mode sensing brush 2a of sensing gear senses various mode operations while coming into contact with the mode sensing pattern of the base plate 1.
On the other hand, FIG. 3 is a perspective view of the conventional cassette holder ejecting unit. In FIG. 3, the reference numeral 4 denotes a main base, 4a a lock pin, 5 a cassette holder, 5a a lock lever, 6 a driving cam gear, 7 an eject lever, and 8 a sensing switch.
As shown in FIG. 3, the driving cam gear 6 and the eject lever 7 are disposed at one side portion of the main base 4, to be engaged with each other. Adjacent to the eject lever 7, the sensing switch 8 is positioned, which is adapted to sense an operation the cassette holder 5. The cassette holder 5 is locked at its closed state, when its lock lever 5a is engaged with the lock pin 4a of main base 4. In opening the cassette holder 5, the lock lever 5a is pushed in the direction indicated by the arrow of FIG. 3 by one end of the eject lever 7 which pivots according to a rotation of the driving cam gear 6. As a result, the lock lever 5a is disengaged from the lock pin 4a, thereby causing the cassette holder 5 to be opened.
In the conventional deck mechanism with the above-mentioned construction, since the mode switch unit and the cassette holder ejecting unit are arranged separately from each other, to be individually driven, the sensing switch operatively connected to the eject lever is arranged to be separated from the mode switch. Such an arrangement requires individual wirings for connecting the switches to the circuit board of apparatus, resulting in a complex wiring arrangement and an increase in number of constituting elements. Moreover, a separate sensing switch is also required. As a result, the overall construction becomes complex, resulting in degradations in workability in assembling and productivity and an increase in manufacture cost.